Physiologic and pharmacologic actions of HANP and HBNP in patients with congestive heart failure will be investigated, including the hemodynamic neurohormonal and renal effects of NP's in heart failure. In addition the proposed effect of NP's to inhibit the adrenergic nervous system will be studied using measures of central sympathetic outflow (microneurograph) and neuronal epinephrine release and reuptake (tripe isotope method).